/* ============================================
   成都炎黄创想科技有限公司 — 蓝白配色
   ============================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --blue: #2563eb;
    --blue-d: #1d4ed8;
    --blue-l: #dbeafe;
    --blue-p: #eff6ff;
    --w: #fff;
    --g50: #f9fafb;
    --g100: #f3f4f6;
    --g200: #e5e7eb;
    --g400: #9ca3af;
    --g500: #6b7280;
    --g600: #4b5563;
    --g700: #374151;
    --g800: #1f2937;
    --g900: #111827;
    --r: 10px;
    --sh: 0 1px 3px rgba(0,0,0,.06);
    --sh-md: 0 4px 16px rgba(0,0,0,.08);
    --t: .25s ease;
}

html { scroll-behavior: smooth; scroll-padding-top: 72px; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    font-size: 16px; line-height: 1.7; color: var(--g600); background: var(--w);
    -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.container { max-width: 1140px; margin: 0 auto; padding: 0 24px; }

/* --- Shared --- */
.sec-head { text-align: center; margin-bottom: 48px; }
.sec-title { font-size: 32px; font-weight: 800; color: var(--g900); letter-spacing: -.5px; margin-bottom: 10px; }
.sec-desc { font-size: 17px; color: var(--g500); max-width: 560px; margin: 0 auto; }

.btn { display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 12px 30px; border-radius: 50px; font-size: 15px; font-weight: 600; transition: all var(--t); border: 2px solid transparent; white-space: nowrap; cursor: pointer; }
.btn-primary { background: var(--blue); color: var(--w); box-shadow: 0 4px 14px rgba(37,99,235,.3); }
.btn-primary:hover { background: var(--blue-d); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(37,99,235,.4); }
.btn-outline { background: transparent; color: var(--blue); border-color: var(--blue); }
.btn-outline:hover { background: var(--blue); color: var(--w); }
.btn-white { background: var(--w); color: var(--blue); box-shadow: 0 4px 14px rgba(0,0,0,.1); }
.btn-white:hover { background: var(--g100); transform: translateY(-2px); }

/* --- Header --- */
.header { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; background: rgba(255,255,255,.92); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border-bottom: 1px solid transparent; transition: all var(--t); }
.header.scrolled { border-bottom-color: var(--g200); box-shadow: var(--sh); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }

.logo { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.logo-icon { width: 36px; height: 36px; display: flex; align-items: center; justify-content: center; background: var(--blue); color: var(--w); border-radius: 9px; font-size: 18px; font-weight: 800; flex-shrink: 0; }
.logo-text { display: flex; flex-direction: column; line-height: 1.15; }
.logo-text strong { font-size: 16px; color: var(--g900); }
.logo-text small { font-size: 10px; color: var(--g400); letter-spacing: .5px; }

.nav { display: flex; gap: 4px; }
.nav-link { padding: 8px 16px; border-radius: 50px; font-size: 15px; font-weight: 500; color: var(--g600); transition: all var(--t); }
.nav-link:hover, .nav-link.active { color: var(--blue); background: var(--blue-p); }

.menu-btn { display: none; flex-direction: column; gap: 5px; padding: 8px; background: none; border: none; cursor: pointer; }
.menu-btn span { display: block; width: 22px; height: 2px; background: var(--g700); border-radius: 2px; transition: all var(--t); }
.menu-btn.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-btn.open span:nth-child(2) { opacity: 0; }
.menu-btn.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* --- Hero --- */
.hero { position: relative; padding: 120px 0 80px; background: linear-gradient(160deg, #eff6ff 0%, #dbeafe 60%, #bfdbfe 100%); overflow: hidden; }
.hero-inner { position: relative; z-index: 2; display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.hero-text { text-align: left; }
.hero-title { font-size: 36px; font-weight: 900; color: var(--g900); letter-spacing: -1px; margin-bottom: 16px; line-height: 1.25; }
.hero-title span { color: var(--blue); }
.hero-sub { font-size: 17px; color: var(--g600); margin-bottom: 10px; line-height: 1.6; }
.hero-desc { font-size: 16px; color: var(--g500); margin-bottom: 32px; }
.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; }

/* Hero floating animation */
.hero-graphic { position: relative; display: flex; align-items: center; justify-content: center; height: 320px; }
.hg-box { position: absolute; border-radius: 20px; box-shadow: 0 10px 40px rgba(37,99,235,.2); }
.hg-1 { width: 160px; height: 160px; background: var(--blue); top: 30px; left: 20px; animation: float 6s ease-in-out infinite; }
.hg-2 { width: 110px; height: 110px; background: rgba(37,99,235,.25); top: 110px; right: 20px; animation: float 6s ease-in-out 1.5s infinite; }
.hg-3 { width: 90px; height: 90px; background: rgba(37,99,235,.45); bottom: 40px; left: 100px; animation: float 6s ease-in-out 3s infinite; }
.hg-circle { position: absolute; width: 55px; height: 55px; background: var(--w); border-radius: 50%; box-shadow: 0 4px 20px rgba(0,0,0,.1); top: 60px; right: 60px; animation: float 6s ease-in-out 1s infinite; }

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-18px); }
}
.hero-title { font-size: 36px; font-weight: 900; color: var(--g900); letter-spacing: -1px; margin-bottom: 16px; line-height: 1.25; }
.hero-title span { color: var(--blue); }
.hero-sub { font-size: 17px; color: var(--g600); margin-bottom: 10px; line-height: 1.6; }
.hero-desc { font-size: 16px; color: var(--g500); margin-bottom: 32px; }
.hero-btns { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

/* --- Services --- */
.services { padding: 90px 0; background: var(--w); }
.svc-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.svc-card { background: var(--w); border: 1px solid var(--g100); border-radius: var(--r); padding: 32px 24px; transition: all var(--t); }
.svc-card:hover { border-color: var(--blue-l); box-shadow: var(--sh-md); transform: translateY(-3px); }
.svc-icon { width: 50px; height: 50px; display: flex; align-items: center; justify-content: center; background: var(--blue-p); border-radius: 8px; color: var(--blue); margin-bottom: 18px; }
.svc-icon svg { width: 28px; height: 28px; }
.svc-card h3 { font-size: 18px; font-weight: 700; color: var(--g800); margin-bottom: 8px; }
.svc-card p { font-size: 14px; color: var(--g500); line-height: 1.7; }

/* --- IoT 物联应用 --- */
.iot { padding: 90px 0; background: var(--w); }
.iot-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.iot-card { background: var(--g50); border-radius: var(--r); padding: 32px 24px; transition: all var(--t); border: 1px solid transparent; }
.iot-card:hover { border-color: var(--blue-l); background: var(--w); box-shadow: var(--sh-md); transform: translateY(-3px); }
.iot-card h3 { font-size: 18px; font-weight: 700; color: var(--g800); margin-bottom: 8px; }
.iot-card p { font-size: 14px; color: var(--g500); line-height: 1.7; }
@media (max-width: 900px) { .iot-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 700px) { .iot-grid { grid-template-columns: 1fr; } }

/* --- Cases --- */
.cases { padding: 90px 0; background: var(--g50); }
.cases-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.case-item { text-align: center; padding: 32px 20px; border-radius: var(--r); background: var(--w); border: 1px solid var(--g100); transition: all var(--t); }
.case-item:hover { border-color: var(--blue-l); box-shadow: var(--sh-md); }
.case-icon { width: 52px; height: 52px; margin: 0 auto 16px; display: flex; align-items: center; justify-content: center; background: var(--blue-p); border-radius: 50%; color: var(--blue); }
.case-icon svg { width: 26px; height: 26px; }
.case-item h4 { font-size: 16px; font-weight: 700; color: var(--g800); margin-bottom: 6px; }
.case-item p { font-size: 14px; color: var(--g400); }

/* --- About --- */
.about { padding: 90px 0; background: var(--w); }
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.about-lead { font-size: 17px; color: var(--g600); font-weight: 500; margin: 20px 0 14px; }
.about-text { font-size: 15px; color: var(--g500); line-height: 1.8; margin-bottom: 28px; }
.stats { display: flex; gap: 36px; }
.stat { text-align: center; }
.stat span:first-child { display: block; font-size: 32px; font-weight: 800; color: var(--blue); }
.stat span:last-child { font-size: 13px; color: var(--g400); margin-top: 2px; }
.values { display: flex; flex-direction: column; gap: 16px; }
.val-card { background: var(--g50); padding: 22px 24px; border-radius: var(--r); border-left: 4px solid var(--blue); transition: transform var(--t); }
.val-card:hover { transform: translateX(5px); }
.val-card h4 { font-size: 16px; font-weight: 700; color: var(--g800); margin-bottom: 4px; }
.val-card p { font-size: 14px; color: var(--g400); }

/* --- Process --- */
.process { padding: 90px 0; background: var(--white); }
.flow { display: flex; align-items: flex-start; justify-content: center; }
.flow-step { text-align: center; flex: 1; max-width: 180px; }
.flow-num { width: 46px; height: 46px; margin: 0 auto 12px; display: flex; align-items: center; justify-content: center; background: var(--blue); color: var(--w); border-radius: 50%; font-size: 18px; font-weight: 700; }
.flow-step h4 { font-size: 15px; font-weight: 700; color: var(--g800); margin-bottom: 4px; }
.flow-step p { font-size: 13px; color: var(--g400); }
.flow-line { flex: 0 0 56px; height: 2px; background: var(--g200); margin-top: 22px; }

/* --- Contact --- */
.contact { padding: 90px 0; background: var(--g50); }
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; }
.contact-info { display: flex; flex-direction: column; gap: 20px; }
.ci-item { display: flex; align-items: flex-start; gap: 14px; }
.ci-icon { width: 44px; height: 44px; flex-shrink: 0; display: flex; align-items: center; justify-content: center; background: var(--w); border-radius: 8px; color: var(--blue); }
.ci-icon svg { width: 20px; height: 20px; }
.ci-item h4 { font-size: 14px; font-weight: 600; color: var(--g900); margin-bottom: 2px; }
.ci-item a, .ci-item span { font-size: 15px; color: var(--g600); }
.ci-item a:hover { color: var(--blue); }

.contact-card { background: linear-gradient(135deg, var(--blue), var(--blue-d)); border-radius: var(--r); padding: 44px 36px; color: var(--w); text-align: center; box-shadow: 0 10px 40px rgba(37,99,235,.3); }
.contact-card h3 { font-size: 22px; font-weight: 700; margin-bottom: 8px; }
.contact-card > p { font-size: 15px; opacity: .85; margin-bottom: 24px; }
.cc-wechat { font-size: 14px; opacity: .85; margin-top: 14px; }
.cc-wechat strong { font-weight: 600; }

/* --- Footer --- */
.footer { background: var(--g900); color: var(--g400); padding: 56px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; padding-bottom: 36px; border-bottom: 1px solid rgba(255,255,255,.08); }
.flogo { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.flogo .logo-text strong { color: var(--w); }
.footer-brand p { font-size: 14px; line-height: 1.7; }
.footer-links { display: flex; flex-direction: column; gap: 10px; }
.footer-links h4 { font-size: 15px; font-weight: 600; color: var(--w); margin-bottom: 6px; }
.footer-links a, .footer-links span { font-size: 14px; transition: color var(--t); }
.footer-links a:hover { color: var(--w); }
.footer-bot { display: flex; justify-content: space-between; align-items: center; padding: 20px 0; font-size: 13px; }
.footer-bot a { transition: color var(--t); }
.footer-bot a:hover { color: var(--w); }

/* ========================================
   RESPONSIVE
   ======================================== */
@media (max-width: 900px) {
    .svc-grid, .cases-grid, .iot-grid { grid-template-columns: repeat(2, 1fr); }
    .about-grid { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 700px) {
    .menu-btn { display: flex; }
    .nav { position: fixed; top: 64px; left: 0; right: 0; background: var(--w); border-bottom: 1px solid var(--g200); padding: 12px 24px; flex-direction: column; gap: 2px; box-shadow: var(--sh-md); transform: translateY(-120%); opacity: 0; transition: all var(--t); }
    .nav.open { transform: translateY(0); opacity: 1; }
    .nav-link { padding: 12px 16px; border-radius: 8px; }

    .hero-inner { grid-template-columns: 1fr; }
    .hero-text { text-align: center; }
    .hero-btns { justify-content: center; }
    .hero-graphic { display: none; }

    .svc-grid, .cases-grid, .iot-grid { grid-template-columns: 1fr; }
    .flow { flex-direction: column; align-items: center; gap: 16px; }
    .flow-line { width: 2px; height: 28px; flex: 0 0 auto; margin: 0; }
    .flow-step { max-width: 100%; }

    .footer-grid { grid-template-columns: 1fr; gap: 28px; }
    .footer-bot { flex-direction: column; gap: 6px; text-align: center; }
    .stats { gap: 20px; }
    .stat span:first-child { font-size: 26px; }
    .contact-card { padding: 32px 24px; }
}